Project A4 (finished)

Background and Motivation

The principal aim of the project is the development of a computational procedure to analyse hydrodynamic interaction effects, i.e. propeller/hull/rudder or propeller/aft-flow-mainpulation devices. Attention is given to the opportunity for a rapid analysis of design changes using overset meshes in combination with adaptive grids for the focal regions

Aims and Objectives

At present, sliding-interface methods are predominantly used for the propulsor analysis. When attention is directed to an assessment of more unconventional propulsors, e.g. cycloidal drives, the flexibility requirements on the meshing approach are significantly enhanced. In order to reduce the associated efforts without compromising the predictive accuracy and to maintain a fair comparability between different configurations during a concept study, overset techniques seem an alternate promising approach. Another area, where overset meshes are beneficial is the simulation of propeller-hull-rudder interaction and related parameter studies, e.g. into the respective influence of the propeller-rudder clearance or the location of energy saving devices. The respective component meshes can be generated at moderate effort since no further geometrical restrictions need to be considered. Moreover, they can be re-used for the parameter studies.

A robust and accurate overset-mesh technology for unstructured grids enhances the state-of-the-art possibilities of fluid-dynamic simulation tools and might facilitate a significant speed up of the design cycle. These benefits are traded against a number of computational challenges which the subject of the present research.Specific emphasis is give to data-management, the conservation of mass and momentum for multiple overset domains, a strong coupling into one equation system as well as the development of a load ballanced parallelisation strategy in conjunction with the dynamic data structures.